缘生穴子蕨 yuan sheng xue zi jue

Trichomanes contiguum G. Forster, Fl. Ins. Austr. 84. 1786; Ctenopteris contigua (G. Forster) Holttum; Davallia contigua (G. Forster) Sprengel; Lecanopteris formosana Hayata; Polypodium contiguum (G. Forster) J. Smith.

Stipe 2-6 cm, with hairs frequent to dense, short, spreading, simple and 1-forked, solitary, medium to dark reddish brown, up to 0.5 mm. Lamina linear-elliptic, 10-30 × 2-4 cm, acuminate, cuneate or gradually attenuate downward to an undulate and narrow wing along stipe, pinnate or deeply pinnately divided to narrow wing less than 0.5 mm wide along rachis; pinnae widely ascending; largest pinnae linear to narrowly lanceolate, 1.2-3 × 0.2-0.4 cm, dilated at base, obtuse at apex; margins of pinnae entire when sterile, crenate toward soriferous portion when fertile; rachis medium brown or darker, terete at base; costa slightly prominent on both surfaces, or sometimes obscure; veins hidden, usually simple, or rarely 1-forked; hairs simple, solitary or sometimes tufted, and 1- or 2-forked, dark reddish brown, up to 0.6 mm, scattered to frequent on abaxial side of rachis, dense and shorter adaxially, occasional to scattered on abaxial side of costae and margin, occasional to sparse on adaxial side of costae and lamina, hairs absent or occasional to scattered abaxially on lamina. Sori 1 per tooth and/or 1 at apex of pinna, 1-6 on each pinna, sunken in marginal urceolate cavities opening outward, rim of cavity usually with some short simple hairs on abaxial side, very sparse or absent on adaxial side.

On tree trunks and moss-covered rocks in dense mountain forests; 400-2000 m. Guangdong, Hainan, Taiwan, Yunnan [Borneo, S India, Indonesia, Malaysia, New Guinea, Philippines, Sri Lanka, Thailand; Australia, Pacific islands].